The present invention relates to novel 2-(N-substitutedguanidino)-4-heteroarylthiazoles wherein said guanidino group is mono-, di- or trisubstituted and said heteroaryl substituent is an imidazol-4-yl, thiazol-4-yl or 1,2,4-triazol-5-yl group. These compounds have activity as antisecretory agents, histamine-H.sub.2 receptor antagonists and/or as inhibitors of ethanol-induced gastric ulceration, useful in inhibiting (i.e. preventing and treating) peptic ulcers in mammals, including humans.
Chronic gastric and duodenal ulcers, together known as peptic ulcers, are a common ailment for which a variety of treatments, including dietary measures, drug therapy and surgery, may be employed, depending on the severity of the condition. Particularly valuable therapeutic agents useful for the treatment of gastric hyperacidity and peptic ulcers are the histamine-H.sub.2 receptor antagonists, which act to block the action of the physiologically active compound histamine at the H.sub.2 -receptor sites in the animal body and to thereby inhibit the secretion of gastric acid. The determination that many of the present compounds will also inhibit ethanol-induced ulcers in rats, further reflects the clinical value of the present compounds in the inhibition of gastric ulcers.
LaMattina and Lipinski in U.S. Pat. No. 4,374,843 issued Feb. 22, 1983 have disclosed a class of 2-guanidino-4-heteroarylthiazole compounds useful for treatment of gastric hyperacidity and peptic ulcers, said compounds having the formula ##STR2## wherein X is S or NH; Y is CH, CCH.sub.3 or N and R is H, CH.sub.2 OH, (C.sub.1 -C.sub.6)alkyl, Ph(CH.sub.2).sub.x or NH.sub.2 which may be optionally alkylated or acylated; Ph is phenyl or monosubstituted phenyl and x is an integer from 2 to 4.
In U.S. Pat. No. 4,435,396 issued Mar. 6, 1984 to the above inventors, 2-guanidino-4-(2-substituted-amino-4-imidazolyl)thiazoles are disclosed which are of the formula (XIII) wherein X is N, Y is CH and R is NH.sub.2, optionally monosubstituted or disubstituted by certain alkyl or phenylalkyl groups, useful in treatment of peptic ulcers.